BIOL 253 Lab Final Exam UPDATED
ACTUAL Exam Questions and CORRECT
Answers
What are some possible sources of error or variation in each of these techniques of blood
pressure measurement? - CORRECT ANSWER - Noise in the room, faint pulse, etc.
What does auscultation mean? Name two ways we took a palpation reading and two ways we
took an auscultation reading. - CORRECT ANSWER - Auscultation in this labs means we
are listening to the occurrence of sounds to measure blood pressure. Feeling for pulse vs. using a
stethoscope to take blood pressure.
What do the sounds correspond to when a blood pressure is taken? - CORRECT
ANSWER - Korotkoff sounds are caused by turbulent flow through the arteries
Could a finger pulse measurement ever replace the stethoscope in determining diastolic pressure?
- CORRECT ANSWER - No. The pulse recording does not have any obvious feature that
allows diastolic pressure to be identified. Therefore, pulse recordings cannot replace the use of a
stethoscope in determining diastolic pressure.
What happened to the finger pulse amplitude when the arm is held above the head? What do you
think could account for this observation? - CORRECT ANSWER - The finger pulse
amplitude decreases dramatically when the arm is held above the head. The systolic pressure will
be harder to detect, and will be much lower than the blood pressure measurement with the hand
at heart level. The physiological reason for this observation is that the hand is more poorly
perfused when held above the head; so the systolic pressure is decreased by the hydrostatic
pressure due to gravity.
What is pulse pressure and how is it calculated? What was the subject's pulse pressure during
each measurement? - CORRECT ANSWER - Pulse pressure is the difference between the
systolic and diastolic pressure readings. Answers will vary based on volunteer.
, At which speed of pressure release did you get your most accurate reading? Why do you think
that is? What could have accounted for inaccuracies in the other measurements? - CORRECT
ANSWER - The heart rate limits the speed at which you can accurately record the blood
pressure. The cuff needs to be deflated at a rate such that there is time for every heart beat to be
detected as pressure falls. If a heart beat is missed, the pressure reading will be in error.
Why do we need to keep in mind the auscultation gap when using the auscultation method to
determine blood pressure? - CORRECT ANSWER - When inflating the cuff, if you stop
inflating at the auscultation gap you will get a low systolic measurement. If you are deflating the
cuff, if you take a reading at the auscultation gap you will get a higher measurement for diastolic.
You may have experienced difficulty in obtaining a blood pressure measurement when the arm
was held above the head. Can you give a physiological explanation for this? Tip: Why do you
think you experience fatigue when holding something above your head? - CORRECT
ANSWER - It is very difficult to obtain a blood pressure measurement when the arm is
held above the head, because the blood pressure in the arm is much lower when the arm is raised.
Because of this, the arm is poorly perfused which leads to fatigue when one is working with arms
above the head.
How does the blood pressure in the leg compare (both thigh and calf) with that in the volunteer's
arm? Explain your reasoning. - CORRECT ANSWER - With the volunteer standing, blood
pressure is greater in the leg than blood pressure in the arm. This results from the hydrostatic
pressure on the column of blood. When the volunteer is lying down, the arm and leg blood
pressures should be very similar since both are at heart level. Therefore, lower limb blood
pressures must always be measured with the volunteer lying flat; otherwise the blood pressures
will need to be corrected for the hydrostatic pressure.
How does resistance from heart to arm differ from resistance from heart to leg? What most likely
accounts for this difference? What happens to flow rate? - CORRECT ANSWER -
Resistance is likely larger from heart to leg because of the increased distance between heart and
leg vs heart and arm. Diameter of the vessels could also have an effect.
During which phase of respiration can the breath be held longer? Why is this? - CORRECT
ANSWER - Breath can always be held longer after a full inspiration, as the lung in this
situation contains its maximum volume of gas. It is difficult to hold your breath for as long at the
end of expiration because the much smaller volume of gas in the lungs results in a more rapid
ACTUAL Exam Questions and CORRECT
Answers
What are some possible sources of error or variation in each of these techniques of blood
pressure measurement? - CORRECT ANSWER - Noise in the room, faint pulse, etc.
What does auscultation mean? Name two ways we took a palpation reading and two ways we
took an auscultation reading. - CORRECT ANSWER - Auscultation in this labs means we
are listening to the occurrence of sounds to measure blood pressure. Feeling for pulse vs. using a
stethoscope to take blood pressure.
What do the sounds correspond to when a blood pressure is taken? - CORRECT
ANSWER - Korotkoff sounds are caused by turbulent flow through the arteries
Could a finger pulse measurement ever replace the stethoscope in determining diastolic pressure?
- CORRECT ANSWER - No. The pulse recording does not have any obvious feature that
allows diastolic pressure to be identified. Therefore, pulse recordings cannot replace the use of a
stethoscope in determining diastolic pressure.
What happened to the finger pulse amplitude when the arm is held above the head? What do you
think could account for this observation? - CORRECT ANSWER - The finger pulse
amplitude decreases dramatically when the arm is held above the head. The systolic pressure will
be harder to detect, and will be much lower than the blood pressure measurement with the hand
at heart level. The physiological reason for this observation is that the hand is more poorly
perfused when held above the head; so the systolic pressure is decreased by the hydrostatic
pressure due to gravity.
What is pulse pressure and how is it calculated? What was the subject's pulse pressure during
each measurement? - CORRECT ANSWER - Pulse pressure is the difference between the
systolic and diastolic pressure readings. Answers will vary based on volunteer.
, At which speed of pressure release did you get your most accurate reading? Why do you think
that is? What could have accounted for inaccuracies in the other measurements? - CORRECT
ANSWER - The heart rate limits the speed at which you can accurately record the blood
pressure. The cuff needs to be deflated at a rate such that there is time for every heart beat to be
detected as pressure falls. If a heart beat is missed, the pressure reading will be in error.
Why do we need to keep in mind the auscultation gap when using the auscultation method to
determine blood pressure? - CORRECT ANSWER - When inflating the cuff, if you stop
inflating at the auscultation gap you will get a low systolic measurement. If you are deflating the
cuff, if you take a reading at the auscultation gap you will get a higher measurement for diastolic.
You may have experienced difficulty in obtaining a blood pressure measurement when the arm
was held above the head. Can you give a physiological explanation for this? Tip: Why do you
think you experience fatigue when holding something above your head? - CORRECT
ANSWER - It is very difficult to obtain a blood pressure measurement when the arm is
held above the head, because the blood pressure in the arm is much lower when the arm is raised.
Because of this, the arm is poorly perfused which leads to fatigue when one is working with arms
above the head.
How does the blood pressure in the leg compare (both thigh and calf) with that in the volunteer's
arm? Explain your reasoning. - CORRECT ANSWER - With the volunteer standing, blood
pressure is greater in the leg than blood pressure in the arm. This results from the hydrostatic
pressure on the column of blood. When the volunteer is lying down, the arm and leg blood
pressures should be very similar since both are at heart level. Therefore, lower limb blood
pressures must always be measured with the volunteer lying flat; otherwise the blood pressures
will need to be corrected for the hydrostatic pressure.
How does resistance from heart to arm differ from resistance from heart to leg? What most likely
accounts for this difference? What happens to flow rate? - CORRECT ANSWER -
Resistance is likely larger from heart to leg because of the increased distance between heart and
leg vs heart and arm. Diameter of the vessels could also have an effect.
During which phase of respiration can the breath be held longer? Why is this? - CORRECT
ANSWER - Breath can always be held longer after a full inspiration, as the lung in this
situation contains its maximum volume of gas. It is difficult to hold your breath for as long at the
end of expiration because the much smaller volume of gas in the lungs results in a more rapid
